Embodiments of the present disclosure generally relate to radar systems and methods.
Radio detection and ranging (radar) systems generally use radio waves to determine a range, altitude, direction and/or speed of objects. Radar systems may be used to detect aircraft, ships, vehicles, guided missiles, weather, terrain, and the like. In general, a radar transmitter or illuminator includes an antenna that transmits pulses of radio waves or microwaves that encounter and reflect off an object. A portion of the energy of the reflected wave is received by an antenna of a radar receiver.
In a monostatic radar system, the transmitter and receiver are located at the same position (that is, collocated). In contrast, a bistatic radar system includes a transmitter and a receiver at separate and distinct positions. For example, the transmitter and receiver of a bistatic radar system may be separated by hundreds of miles.
In order for a bistatic radar system to operate, the locations of both the transmitter and the receiver are known, whether or not either is moving. For example, in airborne applications, if both the transmitter and the receiver are moving (such as when onboard aircraft), the positions of both the transmitter and the receiver are frequently updated. Once the positions of the transmitter and the receiver are known, the positions of unknown targets with the range of the radar system may be determined.
As can be appreciated, in order for a known bistatic radar system to properly function, the transmitter and the receiver communicate with one another or a remote control center in order to provide position information. As such, the transmitter and the receiver cooperate with one another in such a known bistatic radar system. However, providing a communication system between the transmitter and the receiver increases the cost and complexity of a radar system. Further, if the communication system malfunctions or is inoperative, the entire radar system is also inoperative.
Additionally, if the transmitter and the receiver are controlled by separate and distinct entities, the system may not be able to operate. For example, a radar transmitter may be onboard an aircraft controlled or controlled by a first entity, such as a government, while a radar receiver may be onboard an aircraft controlled or owned by a separate and distinct entity that may or may not be cooperative or friendly with the first entity. In such a scenario, the transmitter may not communicate with the receiver, thereby preventing the receiver from utilizing a bistatic radar system that includes the transmitter.